Performance + diagnostics for combined recipe regression

Already-committed wins on this branch since v0.5.418:
- per-node alpha activation in on_facts_changed (a5eaffef1)
- skip asyncpg reset query on pool release (2a3fefff6)
- process-lifetime cache for find_uid_by_xid + find_access_group (36348c871, ee87a8769)
- inline cProfile + per-GFM CPU/wall + throttle + pool stats (f02fc1611)
- gate cProfile on enable_cprofile_inline, off by default (be65d76b2)
- cluster cProfile capture script with prod denylist + dev allowlist (73617a4be, 53d2fd2ef)
- contract test pinning DFU per-product dedup on Origin-split FPFs (158518767)

cProfile activation requires workflows MR 1054 + tag v0.1.474.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>